Well, the fact that it is a IH 154 Lo-Boy says it will be a 4 cylinder, L head water cooled engine.
That tractor uses essentially the same engine from 1947 through 1980. There were minor changes, piston shape and carburetor made the 1977 and later around 14 HP.
The Lo-Boy variation of the standard cub was introduced in 1955. It has shorter front spindles and the final drive was rotated 90 degrees to lower the tractor 8 inches.
Original color was Red, that changed to Yellow and White in 64, then in 77 they changed it back to Red.
The major changes to the electrical system were made in 1964 and in 1968... Those changes were a switch to 12 volts and then the addition of an electric clutch for the PTO.
There were a few variations in the available attachments that were not interchangeable after 1968 when the offset 'frame' disappeared, and that is when you could have the 154 LoBoy, 184 LoBoy or the 185 LoBoy... These were all the same tractor with some changes made to accommodate different attachments, usually all mowers.
To get to your wiring question... Power comes FROM the large terminal on the starter TO the ignition switch... FROM the switch TO the starter button... FROM the starter button TO the starter relay.
The charging circuit was also fed FROM the ignition switch along with any other accessories like lights and PTO clutch were fed FROM the switch to fuses then the acc..
These are fun little tractors, and are tooooo handy to have around:smile:. any thing else just ask:thumbsup:.
How long has your dad had his Cub? KennyV